Auxiliary hydraulic steering mechanism



Jan. 21,1936.

E. T. HODGE El AL AUXILIARY HYDRAULIC STEERIVNG MECHANISM Original ii dApril 30, 1954 s Sheets- Sheet 1 M O m 5 R y mi N NM w R P WW0 w N MM rM A 1% zmmv W Y u Jan. 21; 1936. v T, HQDGE AL 2,028,451

AUXILIARY HYDRAULIC STEERING MECHANISM I Original Filed April 50, 1934 sSheets-Sheet 2' A TTORNEV 1N VENTORS Jan. 21, 1936. E. T. HODGE r AL2,028,451

AUXILIARY HYDRAULIC STEERING MECHANISM Original Filed April 30, 1954 5Sheets-Sheet 3 IN V15 N TOR S saw/w 79/00::

A ND

A TTORNE Y Patented Jan. 21, 1936 I PATENT, OFFICE AUXILIARY HYDRAULICSTEERING MECHANISM 1 UNITED STATES Edwin T. Hodge Hodge and George F.McDougall, land, 0reg.; said McDougall assignor to Portsaid driginalapplication April 30, 1934, 7 Serial No. 723,218. Divided and thisapplication October 20, 1934, .Serial No. 749,245

13 Claims. (01. 180- 192) This is a divisional application of our joint,

motor devices connected to the steering gear.

thereof.

In a device of the character above indicated it is desirable that thecontrol be and remain at all times under the direct influence of theoperator, that is to say that hydraulic or other power when initiatedmust not assume nor continue a directing influence, but should becapable of shutting itself off at any point where manual force isdiscontinued. It is also desirable to establish a hydraulic lock of themotor devices at the shut-01f point.

An object of this invention is a device wherein the manual portion ofthe apparatus, such as a steering wheel, mayturn as many as two or.

more complete revolutions in order to make maximummovment in onedirection and is in- Y stantly reversible manually; and if the hydraulicapparatus is not operating will be free from mechanlcal or hydraulicdrag.

Another object of the invention is a device which will immediatelyreverse an apparatus such as a valve for controlling expansible motorsfrom any attained position of the manually operated control.

A further object of this invention is a valve control device applied tohand steering gear that permits the hand steering gear to be operated inthe usual way, that is efiective to discontinue or resume its functionat any point within the range of the manual apparatus without inducingdrag.

A further object of this invention is a valve control of the characterdescribed that will not be noisy due to clicking or racheting eflect oithe valve throwing device.

A further object of this invention is to provide a valve control of thecharacter indicat'edin the preceding paragraph that will resume its workwherever it finds the steering gear in case for example the source ofhydraulic power such as a pump, should stop and afterwards start upagain, and all without the manipulation of any part by the user orv anypreparation for such resumption of the function of the power apparatus.I g

These and other objects that will be plain to .those skilled in thehydraulic, art are theg-purposes of. the present invention and explainedin the subjoined specification and particularly pointed out in theclaims appended thereto.

For a full understanding of the invention and its novel featuresreference is made tothe ac- 5 companying drawings in which a preferredform is illustrated, to co-operate with the written description. Thedrawings are in considerable detail and for the most part properlyproportioned but it must beunderstoo'd that this is to the end that thedescription may be better understood and is in no wise intended to laydown a hard and fast plan of construction.

In the drawings: 7 o Fig. I is a plan of the controldevice casing andcontents with the cover removed to show contained mechanismsand with themain control valve attached to same; being partly in section; y

Fig. 11 is a view partly in section on the irregular line IL-II of Fig.I; r

Fig. III 'is'a section on Fig. I and includes the cover in Fi I;

Fig. IV is a view showing part of the front of the case broken away toshow the intermittent gear in substantially the positionit will occupywhen the pinion is moving in the direction of the arrow shown in thisview. A special explanation of'this view will be found in the subjoined30 specification; T

Fig. V is a somewhat diagrammatic figure showing some parts in sectionandthe relation-, ship of the devices shown in I and II to the motorswhich they control and the relationship of the motors to the steeringdevice as a whole.

In Fig. I, numeral i representsa box-like casing with the cover removed,2 represents a steering shaft, 3 represents a pinion made rigid with apart of the steering shaftZ, and 4 represents an intermittent gear shownpartially in section and having one tooth, 5, adapted to engage anytooth of the pinion 3 that may be adjacent, .in either direction;intermittent. gear being here defined as a partial gear designed to gointo andv out of mesh with a mating gear element. o The intermittentgearl is.pivoted on the spindle 6 andhas an arm 1 extending beyond the pivotto engage the motors 20 and H.

The intermittent gear 4is shown inits neutral position. At the left handside of I f'is a valve casing 8 having an inletpipe 9 and 1 an exhaustpipe 10a. Theinlet'pipe 9 will be 55 the line III--III of which wasomitted considenedto represent a sauce of hydraulic power not requiringby-passing; that is to say, hydraulic power which may be arranged with arelief valve or may be so constructed in the. known manner as not torequire one, and 9 will be considered to be a source of hydraulic energyat all times when the pump is running. The pump, not being a part ofthis invention, has not been shown.

Within the valve casing I is'a piston valve 90 in the form of a. shelland 'isprovided with an internal exhaust passage III as shown in dottedoutline. It is operated by the valve stem II ,which is jointed at |2 tothe slide l3 reciprocally movable, in the guide l4 and movable byintermittent gear 4. On opposite sides of the arm I are positioned twosingle acting hydraulic mo- I the pinion inthe;position that ward theteeth of the Jand 3| tors 20 and 2| supplied with hydraulic energythrough the connection 220. which will be presumed to be connected tothe same source as the pipe 9 and therefore under the influence ofhydraulic force at all times when the source of hydraulic energy is.operating.

The hydraulicmotors 26 and 2| consist of cylinders 20a and 2 it withinwhich the plungers 26d and 2|d operate. The plungers 29d and 2|d havealimited stroke fixed by the stop 22 which engages with notches 29b and;2|b; hence they always tend to keep the arm I in the position shown inFig. I and when the tooth 5 is in the positio shown in Fig. IV or in itscompletely reversed position not shown but which will bethe reverse ofthat shown in Fig. IV, the tooth 5 is under the influence of one or theother of the plu'ngers 26d and 2|d and always urged tothe position shownin Fig. I. In Fig. IV it is the motor 2| that is urging the arm 1 backto its central or neutral position and in that figure the plunger 26d isnot operating, being held at its extreme strokeby the stop 22. g 1

Abutting the tooth 5 on each side are plungers 30 and, held by the pins32 and 33, working in the slots 34 and 35, and urged upwardly topinion 3by the springs Positioned below the plungers 36 are'spindles 36 and 39working in dash Pots 49 and 4| (see Fig. I).

-'I'he spindles 38 and 39 will have a clearance 36 and 31.

.of several thousandths of an inch within the bores forming the dashpots 40 and 4|, according tothe dmigners calculations, so that they mayfunction efllciently ashydraulic dash pots, it being understood that theentire casing up to a line well above the top of the tooth 5 will at alltimes be kept fllled with a light oil. 'Vents 4a and 4b confine the dashpot action to that part designated to act as such.

It will be observed from Fig. IV that the top of the plungersare curvedto as near as may be, conform to the arc of the tooth ends of the pinion3 and thus while the pinion 3 is turning in the direction of the arrowshown in Fig. IV thepointofthetoothiwillbecushionedtoa very large extentand when it reaches the point.

shown in Fig. IV it will not snap back abruptly and strike the nexttooth indicated in this view by :r, butthe movement backward will becushioned, and if the pinion turm rapidly, almost imperceptible.

This particular view of Fig. IV is purposely made so thatthe center lineof tersects with the center line of The function of the motors 20 and 2|will be" taken up by the springs 20c and 2 |c which are auxiliary to themotors 26 and 2| and serve to accomplish this function if at any timethe steering device is operated when the source .of hydraulic energy isinoperative.

The steering shaft 2 is constructed after the well known manner and maybe hollow and through the hollow of which may project control memberssuch as the tubes 2a, 2b,-and 20 which may control the throttle, sparklever and contain wiring, and the shaft 2 is mounted after the knownmanner in the steering tube 46 held to the casing by clamps 42 and 42a.The tubes such as 2a, 2b and 2c are continuous through the shaft, whilethe shaft is cut at the point indicated by the dotted lines at 43 andrigidly mounted upon each half of the shaft beyond '43 is a half of thejaw coupling 44 and 45.

The jaw coupling 44 and 45 is made to have a degree of lost-motion,shown at 46, that will be sufficient to allow the pinion 3 to bemanually reversed independently, of the reducing gear 50 (see. Fig. V)so that the intermittent gear 4 may be freely operated to throw thepiston valve 90 from the position indicated in Fig. IV for ex--' ampleto the reverse position that it would occupy 'to steer in the oppositedirection, or if manual force is released, from the shaft 2 the motor 2|may return the intermittent gear to the neutral position shown in Fig. Iand the valve tie to. neutral as in Fig. I. It is also shown in-the samefigure that returning to neutral effects a hydraulic lock of the pipes60 and 6| and the connected motors 62 and 63.

Assuming the hydraulic pressure device diagrammatically indicated by'the numeral 9 to be operating, then no hydraulic fluid can'enter orleave the tubes 60 and 6|, but if the intermittent gear has been movedto the position shown in Fig. IV then hydraulic energy will pass from 9to the annular space 9a, thence past the shoulder of the valve to theannular space M and at the same time the annular space 9e will be incommunication with the interior hollow of the valve l0 and thus incommunication with the exhaust pipe Ina which will form an uninterruptedconduit to a reservoir, not shown, for the pumping device so that thefluid may be returned and used over again.

When energy is supplied to the annular passageway 9d it is effectivethrough the tube 66 which connects to the hydraulic push motor 62 at theleft hand side of Fig. V and when the intermittent gear is in reverseposition to that shown in Fig. IV, then the other hydraulic push motorshown in section at 63 will be energized, while the first named motor 62and its interior will be in direct'communication with the exhaust pipeIlla. and therefore with the reservoir and under a slight staticpressure.

It will be noted that these push motors are single acting and thepistons such as 64 are of the trunk type and without wrist pins but havea socket 65 within which 66 flexibly attached the pivot means 63;

projects a piston rod an it will be understood the steering arm 61 by Iv the steering arm that the other motor 62 is formed as a reverseduplicate. Movement of parts is less than the length of the socket 65.

Should the vehicle to which the steering gear as a whole is attached besteered solely by means of the steering shaft, to operate. the reducinggear 50, (which may be of any type, kind or gear ratio) by hand, andwhich in turn influences the steering arm 61 backward or forward, tosteer the vehicle, then if no hydraulic ,energy is available the piston64, for example, will be easily forced back into its cylinder 63, thecylinder having a free communication with exhaust means to a reservoirand the ,piston 64 will remain where it is left by the pistonrod 66 andthe piston captained in the cylinder 62 under the same conditions willdo the same thing, offering very slight parasitic drag to themovement-of 61 on one occasion and none thereafter.

It may also be noted that when the source of hydraulic energy is oncemore operative that either of the pistons such as 64- will immediatelytake up its position of contact with a piston rod such as 66 uponhydraulic energy being supplied through an appropriate conduit or pipesuch as 60 or iii. 10 represents part of a vehicle frame and Ii is ashaft energized by the reducing gear 50. Reducing'g'ears of most types,especially when made of sufiicient ratio for-a large heavy vehicle arepractically irreversible, hence it will always be necessary man tofurnish enough manual force to overcome the motors 20 and 2| and alsoenough additional force to move the reducing gear 50.

Returning now to Fig. I where the device is shown to be in neutral, itwill be noted that the pinion 3 may be selectively moved by manual meansin either direction and that upon being so moved it will move the valve90 contained within the casing 9 to energize one or the other of thehydraulic motors 62 and 63 according to tains may make and use derassistance in the which direction the pinion is moved.

On the other handif the driver releases his hold on the steering wheelor shaft the hydraulic mechanism will not reverse but will merely cometo neutral owing to the virtues of the push motors 26 and 21 and theirlimited stroke.

It is of course clear that instead of the intermittent gear-beingpivoted it may be an intermittent rack with proper design ofco-operating parts.

The device as illustrated, or its mechanical equivalent, is a strictlyco-operative one tor rensteering but not to carry it on when manualforce, which it supplements,

is withdrawn. The piping shouldbe ample to,

eliminate any drag or obstruction to hand steering when the pump is notrunning. i

Having thus fully disclosed the invention so that those skilled in theart to which it apperit, what is claimed as new and desired to secure byLetters Patent, is,-

1. In an intermittent gear means for operation of a valve, a revolublepinion, an intermittent gear adapted to mesh with said pinion and havinga tooth thereon, movable plungers abutting said tooth to cushionracheting effect of the tooth and pinion and hydraulic motors adapted toremesh the intermittent gear with the pinion.

2. In an intermittent gear means for operation of a valve, a revolublepinion, an intermittent gear adapted to mesh with'said pinion and havinga tooth thereon, movable plungers abutting said tooth to cushi acterdescribed, a, pinion,

for the steersmanually rotatable shaft, a pinion n racheting effect ofthe tooth and pinion and spring means adapted to remesh the intermittentgear with the pinion.

3. In an intermittent gear device of the charan intermeshing partialgear therefor rounded teeth for both ele- 5' ments and hydraulic devicespositioned to oppose movement of the partial gear and effective toprevent teeth on the partial gearand pinion from coming to rest withtheir center lines intersecting.

4. In an intermittent gear device of the character described, a pinion,an intermeshing partial gear therefor, rounded teeth for both elementsand springs pos'tioned to oppose movement of the partial gear andeffective to prevent 5 teeth on the partial gear and pinion. from comingto rest with their center lines intersecting.

5. An intermittent gear device comprising in combination a revolublepinion, an intermittent gear adapted to mesh with said pinion and hav-20 ing a tooth thereon, movable plungers abutting said tooth to cushionracheting effect of the tooth and pinion and hydraulic motors adaptedto, remesh the intermittent gear with the pinion.

6. An intermittent gear device combination. a revoluble pinion, apartial gear adapted to mesh with said pinion and having a tooththereon, movable plungers, abutting said tooth to cushion rachetingeffect of the tooth and pinion and spring means adapted to remesh 30 thepartial gear with the'pinion.

7. A valve control device comprising in combination a revoluble pinion,a partial gear adapted to mesh with said pinion and having a tooththereon, movable plungers abutting said 5 tooth, manual means forrevolving the pinion in either direction and automatic means for resaidpinion, automatic means for remeshing the partial gear with the pinionat any tooth on the perimeter of said pinion and a valve controlled 5 bysaid partial gear.

9. In a valve control device comprising manual means for rotating ashaft and a pinion made rigid therewith, intermittent gear valve controladapted to selectively move a valve by intermittent engagement with thepinion, a pair of hydraulic motors operatively connected to saidintermittent gear and tending to restore the valve to an intermediateneutral position upon cessation of manual force to the shaft rotatingmeans.

10. In a valve control device comprising a made rigid with said shaft,an intermittent gear adapted to engage the pinion during a fractionalpart of a revolution thereof, a valve selectively movable by theintermittent gear in either direction from an intermediate neutralposition and the combination of a pair of hydraulic motors positioned torestore said valve to its neutral position upon cessation of manualforce to said rotatable shaft. M,

position upon cessation of manual force.

12. In a valve control device comprising a 1 comprising in 25 manuallyrotatable shaft and a pinion rotatable thereby, an intermittent gearadapted to be moved in either'direction by the pinion, valve controlmeans movalile by the intermittent gear from-an intermediate neutral toan operative position 'oneither side of neutral and a pair of hydraulicmotors positioned to oppose movement ofthe intermittent .gear in eitherdirection and' tending to restore the valve to neutral by a small 10reverse movement of the intemiittent gear, the

pinion and the manual device upon cessation of 4 manual force.

13. The combination according to claim 12 in which the hydraulic motorsare provided with stroke means restricting the automatic return of thevalve to its intermediate neutral position.

